The US Supreme Court Friday announced it will judge during its present sessions, which end in June, whether all 50 states of the country must allow marriages between same-sex couples.
The justices have resisted deciding on the matter for months, the last time being in October when they refused to hear appeals against a lower court ruling that permitted same-sex marriages in five states.
The Supreme Court will consider four high-profile cases in which courts of appeal upheld the ban on gay marriage in the states of Kentucky, Michigan, Ohio and Tennessee, overturning previous decisions by federal judges supporting equal rights for gay people.
Another 10 states also ban such unions.
Meanwhile, in Arkansas, Mississippi, Missouri, South Dakota and Texas, judges have annulled laws forbidding gay marriage, but they remain in force pending an appeal.
The cases will be tried in the month of April and the final decision of the five conservative and four progressive Supreme Court justices could be handed down in June.
The apex court must determine whether all states of the nation must issue marriage licenses to the same-sex couples and if those licenses must be automatically considered valid in all the other states.